GHC.Prelude

Custom GHC Prelude

This module serves as a replacement for the Prelude module and abstracts over differences between the bootstrapping GHC version, and may also provide a common default vocabulary.

Documentation

module GHC.Prelude.Basic

pprTrace :: String -> SDoc -> a -> a

If debug output is on, show some SDoc on the screen

pprTraceM :: Applicative f => String -> SDoc -> f ()

pprTraceDebug :: String -> SDoc -> a -> a

pprTraceWith :: String -> (a -> SDoc) -> a -> a

pprTraceWith desc f x is equivalent to pprTrace desc (f x) x. This allows you to print details from the returned value as well as from ambient variables.

pprTraceIt :: Outputable a => String -> a -> a

pprTraceIt desc x is equivalent to pprTrace desc (ppr x) x

pprTraceException :: ExceptionMonad m => String -> SDoc -> m a -> m a

pprTraceException desc x action runs action, printing a message if it throws an exception.

pprSTrace :: HasCallStack => SDoc -> a -> a

If debug output is on, show some SDoc on the screen along with a call stack when available.

warnPprTrace :: HasCallStack => Bool -> String -> SDoc -> a -> a

Just warn about an assertion failure, recording the given file and line number.

pprTraceUserWarning :: HasCallStack => SDoc -> a -> a

For when we want to show the user a non-fatal WARNING so that they can report a GHC bug, but don't want to panic.